Around 100 protestors from animal rights groups PETA and AnimaNaturalis called for a stop to bullfighting and bull runs a day before the start of the famous running of the bulls during the San Fermin festival in Pamplona, Spain.

The protestors, wearing nothing but their underwear and fake horns on their head, threw red powder in the air to symbolize the bloodshed brought on by the annual event.

The San Fermin festival brings thousands of people from across the world to run through the streets of Pamplona while being chased by the bulls, which are led to a ring where they are used in bullfights.

Protestors have reportedly shown up every year for the last 14 years to oppose the event, and this year’s protest was the biggest yet.